Buffer for guns



A. M. CRAIG.

BUFFER FOR GUNS.

APPLICATION FILED NOV. 23. 1918.

1,356,191 Patented 0st. 19, 1920..

UNITE- ALVIN 1V1. CRAIG, OF NEW HAVEN, CONNECTICUT.

' BUFFER FOR GUNS.

Specification of Letters Patent.

Patented Oct. 19,1920.

Application filed November 23, 1918. Serial No. 263,803.

T 0 all 20 hom it may concern:

Be it known that I, ALVIN M. CRAIG, a citizen of the United States, anda resident of the city of New Haven, county of New Haven, and State ofConnecticut, have invented a new and useful Improvement in Buffers forGuns, of which the following is a full, clear, and exact description;

My invention relates to improvements in buffers for guns, meaning bythis term to include all varieties of firearms, and the objectof myinvention is to produce a simple device which is applicable to variousstyles of firearms and which is particularly applictble to such guns asemploy a bolt in the receiver, the buffer being adapted to dissipate anddiffuse the shock occasioned by the recoil or backward movement of thebolt. in arms of this type the shock of the bolt as it comes back isdetrimental both to the operator and to its effect on the accuracy ofthe gun. If the gun is a shoulder piece, the blow is such as to make anobjectionable kick which gives to the operator a sore shoulder, andfurthermore the action, es-

pecially on lighter guns, causes the arm to jump so that it isinaccurate in its fire. My invention is intended to overcome thesedifficulties as stated and to produce an extremely simple device whichcan be applied to all firearms of this character, and in which the boltwhen near the limit of its stroke strikes the buffer and the latterwhile having a very small movement, still is able to thoroughly diffuseand dissipate the shock, all of which will be more clearly understoodfrom the description which fol-' lows.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which similar reference characters indicatecorresponding parts in all the views.

Figure 1 is a longitudinal section of the invention showing itsapplication to a part of a, receiver and bolt of a gun, and with theparts in the position they assume before the bolt has struck the bufier.

Fig. 2 is a similar view but with the bolt in contact with the bufi'erand the latter pushed back to its limit, and

Fig. 3 is a cross section on the line 33 of Fig. 2. v

The bolt 10 can be an conventional or preferred type of bolt whichslides in a casing 11 which represents a portion of a receiver, or atleast a casing which is made toreceive the rear end of the bolt. Asecond casing 12 which is shown in the form of a nut, is attached to thecasing 11, the drawing showing the member 12 screwing into the member11, and this member 12 has a socket portion 14 initsfront end to receivethe head 15 of the buffer, thebody portion 16 of the buffer slidingthrough or in the member 12, and the body portion 16 has preferablyflat-. toned sides in which are sockets 17 to receive the balls'18, thelatter extending for only a portion of their radii into the sockets andrunning in ways 19 which are made transversely in a wall of the, member12. The balls 18 are pressed to their seats in the member 16 by springs20, and the sprin s can be held in any convenient way. s

shown a cap 21 screws to the member 12 and covers the several ways 19. i

Obviously the member 16 c desired cross sectional shape, and the buffercan be of one diameter throughout instead of having the head 15, but theportion in which the sockets 17 are located is preferably flattened atthe points where the sockets are made because in this way I get a betterbearing surface of the walls of the socket on the balls, andconsequently a better action of the buffer.

When the buffer is in its forward position shown in Fig. 1, the severalballs 18 which may or may not be in alinement, are pressed into thesockets 17 preferably for about twofifths of the diameter of the balls.jWhen the bolt 10 strikes the buffer head 15, the bufier is pushed backslightly and the walls of the sockets 17 pressing against theballs 18vcause the latter to turn and move outward slightly against the tensionof their springs-20. I have found in actual practice that the resilienceof the buffer is not dependent entirely on the springs 20, but that theshock appears to be dissipated by the rotation of the balls, though thesprings also have their cushioning effect. The invention is applicableto various sizes of guns or bolts, and to diffuse thrusts of varyingforce because the balls can be made larger or smaller and the springs 20stiffer or li hter as desired.

The experiments which have been made with the buffer have been entirelysatisfactory, and in such experiments balls have an be of any been usedas the connecting medium between the walls of the bufler and the socketsin the latter.

. The balls are set so that they never leave their seats in the sockets,although they do yield slightly against the pressure of their springs,but they spin when under the impact of the blow which tends to force thebuffer lengthwise. In this way the energy of the blow is dissipated ordiffused in the spinning of the balls which constantly pre- I seats. andyet yield slightly against their springs, the shock against the bufferis diffused with a very slight longitudinal movement of the buffer. Thishas been demonstrated by thousands of experiments, and in a gun theshock occasioned by the rearward movement of the bolt is-practic allyall. dissipated or diffused, and Iha've found further that where thereis a very heavy shock several 'of'these buffers may be used, one behindthe other. so that the slight movement of one will be in part taken upby the one, behindit, but the buffers are made as shown and I refer tothis simply to illustrate a more extended use of the structure. 7

In guns of the kind here referred to attention is called to the factthat the rear end of the bolt besides making the gun objectionable forthe reasons already pointed out, is apt to become itself battered anduseless after a short time because of its violent thrust against thepart behind it; but with the buffer described the rear end'of the boltis left uninjured, and a further advantage is that the action of the guncan be slowed or quickened by regulating the springs 20 behind the balls18, that is if relatively stiff springs are used the action will bespeeded because of the quick, sharp reaction of the springs, and iflighter springs are used the action will be retarded. This regulation ofthe speed can be further governed by regulating the depth of the ballseats in the bufffer body, as obviously the ball will release quicker ifthe seat is shallow than it will if the seat is deeper.

I claim 1. A buffer of the kind described compris- 7' 2. A buffer of thekind described comprising acasing, a member sliding longitudi-' nally inthe casing and provided with flattened sides having sockets therein, andcushioned balls held transversely in the casing and entering theaforesaid sockets sufiiciently far to retaintheir seats when the bufferis subjected to endwise movement but to turn in said sockets.

A buffer of the kind described comprising a longitudinally slidingmember having a guided movement and surface sockets therein, andcushioned balls held opposite the sliding member and entering thesockets sufliciently to retain their seats when the sliding member. issubjected to endwise movement.

4. A buffer of the kind described comprising a sliding member having anenlarged head and sockets in its side surface, a casing fitting thesliding member, and cushioned balls arranged transversely in the casingand enter-ing the aforesaid sockets sufficiently to retain their seatsunder any endwise movement of the sliding member but to turn in theirseats. V

5. The combination with the sliding bolt and a receiver for the rearendportionof the bolt, of a sliding buffer arranged behind the bolt inpositionto receive the thrust of the latter,.said buffer having. socketsin its sides, and cushioned'rotary members held opposite the buffer andentering the aforesaidsockets sufiiciently to retain their seatsunder'the endwise movement ofthe'buffer but to rotate in said seats. -I

ALVIN M. CRAIG. Witnesses: V

WARREN B. HUToHINsoN,

G. ODQNNELL.

